1. Live Attenuated Vaccines – Contain weakened (attenuated) forms of the virus or bacteria (e.g., measles, mumps, rubella (MMR) vaccine).
2. Inactivated Vaccines – Contain killed (inactivated) viruses or bacteria (e.g., polio vaccine).
3. Subunit, Recombinant, Polysaccharide, and Conjugate Vaccines – Contain only specific parts of the virus or bacteria (e.g., HPV vaccine, hepatitis B vaccine).
4. Toxoid Vaccines – Contain inactivated toxins produced by bacteria (e.g., diphtheria and tetanus vaccines).mRNA Vaccines – Contain genetic instructions for cells to produce a harmless piece of the virus (e.g., COVID-19 vaccines like Pfizer and Moderna).
5. Viral Vector Vaccines – Use a harmless virus to deliver genetic instructions to cells (e.g., AstraZeneca and Johnson & Johnson COVID-19 vaccines).